Reply to Vci 100mk2 aux not working??

I want to be able to use an iPod as a sound bank so if someone was to give me their iPod I could plug it in to my system. I have tried the auxiliary input and my lap top is recieving the signal (tractor le) but im not getting any sound. In fact the same thing is happening when I plug in a cd player or mic into my aux input? Please help